"""Tests for the experiment-governance workflow state machine."""

from __future__ import annotations

import pytest

from spinor_os.config import AttributionMethod, Direction, EventType, LoopStage, MaturityStage
from spinor_os.models import (
    AttributionClaim,
    Event,
    Experiment,
    Hypothesis,
    Mission,
    PredictedEffect,
)
from spinor_os.workflow import (
    ExperimentGovernanceWorkflow,
    WorkflowContext,
    WorkflowTransitionError,
)


def make_hypothesis() -> Hypothesis:
    return Hypothesis(
        statement="X increases Y",
        causal_claim="X causes Y to increase.",
        falsification_criteria=["Y does not increase"],
        predicted_effect=PredictedEffect(
            metric="y_rate",
            direction=Direction.INCREASE,
            magnitude=0.1,
            unit="pp",
            timing="7d",
            confidence=0.9,
        ),
        employee_owner="emp-001",
    )


def make_context(stage: LoopStage, **overrides) -> WorkflowContext:
    hypothesis = make_hypothesis()
    experiment = Experiment(hypothesis_id=hypothesis.hypothesis_id)
    experiment.set_stage(stage)
    return WorkflowContext(
        experiment=experiment,
        hypothesis=hypothesis,
        **overrides,
    )


def test_allowed_next_from_research():
    wf = ExperimentGovernanceWorkflow()
    next_stages = wf.get_allowed_next(LoopStage.RESEARCH)
    assert LoopStage.ALLOCATE in next_stages
    assert LoopStage.DISASSEMBLE in next_stages


def test_invalid_transition_raises():
    wf = ExperimentGovernanceWorkflow()
    ctx = make_context(LoopStage.RESEARCH)
    with pytest.raises(WorkflowTransitionError):
        wf.advance(LoopStage.RESEARCH, LoopStage.SYSTEMIZE, ctx)


def test_gates_require_mission_before_execute():
    wf = ExperimentGovernanceWorkflow()
    ctx = make_context(LoopStage.ALLOCATE)
    ok, reason = wf.can_advance(LoopStage.ALLOCATE, LoopStage.EXECUTE, ctx)
    assert not ok
    assert "mission" in reason.lower()


def test_gates_require_events_before_observe():
    wf = ExperimentGovernanceWorkflow()
    ctx = make_context(LoopStage.EXECUTE)
    mission = Mission(
        experiment_id=ctx.experiment.experiment_id,
        hypothesis_id=ctx.hypothesis.hypothesis_id,
        employee_id="emp-001",
        modification="mod",
        customer_segment="a",
        territory="b",
        timing="c",
    )
    ctx.mission = mission
    ok, _ = wf.can_advance(LoopStage.EXECUTE, LoopStage.OBSERVE, ctx)
    assert not ok


def test_falsify_to_replicate_requires_significant_claim():
    wf = ExperimentGovernanceWorkflow()
    hypothesis = make_hypothesis()
    experiment = Experiment(hypothesis_id=hypothesis.hypothesis_id)
    experiment.set_stage(LoopStage.ATTRIBUTE)
    claim = AttributionClaim(
        experiment_id=experiment.experiment_id,
        hypothesis_id=hypothesis.hypothesis_id,
        outcome_metric="y_rate",
        outcome_value=0.05,
        counterfactual_estimate=0.01,
        method=AttributionMethod.RCT,
        confidence=0.4,
        falsification_survived=True,
    )
    ctx = WorkflowContext(experiment=experiment, hypothesis=hypothesis, claim=claim)
    ok, _ = wf.can_advance(LoopStage.ATTRIBUTE, LoopStage.FALSIFY, ctx)
    assert ok

    # Advance to falsify first.
    wf.advance(LoopStage.ATTRIBUTE, LoopStage.FALSIFY, ctx)
    # Then try to replicate with a non-significant claim.
    experiment.set_stage(LoopStage.FALSIFY)
    with pytest.raises(WorkflowTransitionError):
        wf.advance(LoopStage.FALSIFY, LoopStage.REPLICATE, ctx)


def test_suggest_next_falsify_significant():
    wf = ExperimentGovernanceWorkflow()
    hypothesis = make_hypothesis()
    experiment = Experiment(hypothesis_id=hypothesis.hypothesis_id)
    experiment.set_stage(LoopStage.FALSIFY)
    claim = AttributionClaim(
        experiment_id=experiment.experiment_id,
        hypothesis_id=hypothesis.hypothesis_id,
        outcome_metric="y_rate",
        outcome_value=0.2,
        counterfactual_estimate=0.05,
        method=AttributionMethod.RCT,
        confidence=0.95,
        falsification_survived=True,
    )
    ctx = WorkflowContext(experiment=experiment, hypothesis=hypothesis, claim=claim)
    assert wf.suggest_next(ctx) == LoopStage.REPLICATE